Abstract: A fuel injector for a turbine engine includes a fuel scheduling valve configured for regulation of fuel flow from a fuel inlet, in response to fuel pressure received at the fuel inlet. Primary, secondary and auxiliary fuel circuits receive fuel from the scheduling valve, and an electrically-controlled valve is provided in fluid communication with the auxiliary circuit, which electrically-controlled valve is adapted and configured to actively control fuel through the auxiliary circuit in response to a control signal.

Abstract: A fuel injector for a turbine engine includes a fuel scheduling valve configured for regulation of fuel flow from a fuel inlet in response to fuel pressure received at the fuel inlet. Primary and secondary fuel circuits receive fuel from the scheduling valve, and an electrically-controlled valve is provided in fluid communication with the primary circuit, adapted and configured to actively control fuel through the primary circuit in response to a control signal.

Abstract: A system includes an injector having a scheduling valve assembly and a nozzle in fluid communication with the valve assembly. The scheduling valve assembly is configured for regulation of flow from an inlet of the injector to the nozzle. An electromagnetic device is operatively connected to a hydromechanical valve spool of the valve assembly to selectively adjust position of the valve spool in the valve assembly.

Abstract: A system includes an injector having a scheduling valve assembly and a nozzle in fluid communication with the valve assembly. The scheduling valve assembly is configured for regulation of flow from an inlet of the injector to the nozzle. The injector includes two fluid circuits between the inlet of the injector and two respective outlets of the nozzle for staged flow output from the nozzle. A first one of the two fluid circuits is a primary circuit, and a second one of the two fluid circuits is a secondary circuit. A solenoid valve is connected in fluid communication with the scheduling valve assembly, wherein the solenoid valve is configured to adjust position of a hydromechanical valve spool of the valve assembly.

Abstract: A fuel injector for a turbine engine includes a fuel scheduling valve configured for regulation of fuel flow from a fuel inlet in response to fuel pressure received at the fuel inlet. Primary and secondary fuel circuits receive fuel from the scheduling valve, and an electrically-controlled valve is provided in fluid communication with the primary circuit, adapted and configured to actively control fuel through the primary circuit in response to a control signal.

Abstract: A system includes an injector having a scheduling valve assembly and a nozzle in fluid communication with the valve assembly. The scheduling valve assembly is configured for regulation of flow from an inlet of the injector to the nozzle. The injector includes two fluid circuits between the inlet of the injector and two respective outlets of the nozzle for staged flow output from the nozzle. A first one of the two fluid circuits is a primary circuit, and a second one of the two fluid circuits is a secondary circuit. A solenoid valve is connected in fluid communication with the scheduling valve assembly, wherein the solenoid valve is configured to adjust position of a hydromechanical valve spool of the valve assembly.

Abstract: A system includes an injector including a scheduling valve assembly and a nozzle in fluid communication with the valve assembly. The scheduling valve assembly is configured for regulation of flow from an inlet of the injector to the nozzle. The injector includes one fluid circuit between the inlet of the injector and a respective outlet of the nozzle. A solenoid valve is connected in fluid communication with the scheduling valve assembly. The solenoid valve is configured to adjust position of a hydromechanical valve spool of the valve assembly.

Abstract: A fuel injector for a turbine engine includes a fuel scheduling valve configured for regulation of fuel flow from a fuel inlet in response to fuel pressure received at the fuel inlet. Primary and secondary fuel circuits receive fuel from the scheduling valve, and an electrically-controlled valve is provided in fluid communication with the primary circuit, adapted and configured to actively control fuel through the primary circuit in response to a control signal.

Abstract: A system includes an injector having a scheduling valve assembly and a nozzle in fluid communication with the valve assembly. The scheduling valve assembly is configured for regulation of flow from an inlet of the injector to the nozzle. The injector includes two fluid circuits between the inlet of the injector and two respective outlets of the nozzle for staged flow output from the nozzle. A first one of the two fluid circuits is a primary circuit, and a second one of the two fluid circuits is a secondary circuit. A solenoid valve is connected in fluid communication with the scheduling valve assembly, wherein the solenoid valve is configured to adjust position of a hydromechanical valve spool of the valve assembly.

Abstract: A fuel system can include a total flow line configured to receive a total flow and a primary flow line connected to the total flow line. The primary flow line can be in fluid communication with one or more primary fuel nozzles of a nozzle assembly. The fuel system can include a secondary flow line connected to the total flow line in parallel with the primary flow line, the secondary flow line in fluid communication with a plurality of secondary flow nozzles of the nozzle assembly. The fuel system can include a flow split system configured to control a flow split between a primary flow of the primary flow line and a secondary flow of the secondary flow line.

Abstract: In accordance with at least one aspect of this disclosure, a fuel system can include, a fuel device, a fuel characterization device operatively connected to the fuel device configured to measure performance data of the fuel device before installation into an engine fuel system, and an electronic engine controller operatively connected to the fuel characterization device to receive the measured performance data of the fuel device on start up and calculate a metered mass flow based at least in part on the measured performance data of the fuel device. The electronic engine controller can be configured to control the fuel device to direct, meter, or pump fuel to the engine through the fuel device based on the calculated metered mass flow.

Abstract: A fluid injection system can include a main flow line, a primary flow line connected to the main flow line, and a primary flow valve disposed between the primary flow line and the main flow line and configured to allow injectant flow to the primary flow line from the main flow line in an open primary flow valve state, and to prevent injectant flow to the primary flow line from the main flow line in a closed primary flow valve state. The system can include a secondary flow line connected to the main flow line and a secondary flow valve disposed between the secondary flow line and the main flow line and configured to selectively allow injectant flow to the secondary flow line from the main flow line in an open secondary flow valve state, and to prevent injectant flow to the secondary flow line from the main flow line in a closed secondary flow valve state.

Abstract: A system includes a flow inlet conduit and a primary conduit that branches from the flow inlet conduit for delivering flow to a set of primary nozzles. An equalization bypass valve (EBV) connects between the flow inlet conduit and a secondary conduit for delivering flow to a set of secondary nozzles. The EBV is connected to an equalization conduit (EC). A pressure equalization solenoid is connected to the EC to selectively connect a servo supply pressure conduit and/or a return pressure (PDF) conduit into fluid communication with the EC. An EBV rate limiting orifice (RLO) is connected in the PDF conduit. A bypass conduit branches from the PDF conduit on a first side of the EBV RLO and reconnects to the PDF conduit on a second side of the EBV RLO. An orifice bypass valve (OBV) is connected to the bypass conduit and acts to selectively bypass the EBV RLO.

Abstract: Apparatus and associated methods relate to simultaneously pumping and measuring density of an aircraft fuel. The aircraft fuel is pumped by a centrifugal pump having an impeller. A rotational frequency of the impeller is determined while the centrifugal pump is pumping the aircraft fuel. Flow rate of the aircraft fuel through the centrifugal pump is sensed. Pressure of the aircraft fuel is measured at two different points within or across the centrifugal pump or a differential pressure is measured between the two different points while the centrifugal pump is pumping the aircraft fuel. Density of the aircraft fuel is determined based on a head-curve relation characterizing the centrifugal pump. The head-curve relation relates the fuel density to the rotational frequency, the flow rate, and pressures at the two different points or the differential pressure between the two different points.

Abstract: A fuel system including a fuel tank, a first pump fluidly coupled to the fuel tank configured for distributing fuel from the fuel tank throughout the fuel system, and a second pump fluidly coupled to the first pump by a pressure regulating valve and configured for driving fuel to an engine.

Abstract: Apparatus and associated methods relate to simultaneously pumping and measuring density of an aircraft fuel. The aircraft fuel is pumped by a centrifugal pump having an impeller. A rotational frequency of the impeller is determined while the centrifugal pump is pumping the aircraft fuel. Flow rate of the aircraft fuel through the centrifugal pump is sensed. Pressure of the aircraft fuel is measured at two different points within or across the centrifugal pump or a differential pressure is measured between the two different points while the centrifugal pump is pumping the aircraft fuel. Density of the aircraft fuel is determined based on an empirically-determined head-curve relation corresponding to the centrifugal pump. The head-curve relation is empirically determined during a characterization phase. The empirically-determined head-curve relation relates the density of the aircraft fuel to the rotational frequency, the flow rate, and the pressures at the two different points.

Abstract: A fuel delivery system for a gas turbine engine is disclosed which includes a continuously variable drive assembly having a driving portion operatively associated with a gearbox of the gas turbine and a driven portion operatively associated with a fuel pump of the gas turbine, and a governor for controlling a drive ratio of the drive assembly to vary fuel pump flow performance over a range of engine operating conditions.

Abstract: A fuel system can include a total flow line configured to receive a total flow and a primary flow line connected to the total flow line. The primary flow line can be in fluid communication with one or more primary fuel nozzles of a nozzle assembly. The fuel system can include a secondary flow line connected to the total flow line in parallel with the primary flow line, the secondary flow line in fluid communication with a plurality of secondary flow nozzles of the nozzle assembly. The fuel system can include a flow split system configured to control a flow split between a primary flow of the primary flow line and a secondary flow of the secondary flow line.

Abstract: A method can include receiving, at a control module, first pump characteristic data from a data source associated with a pump, sensing second pump characteristic data from a flow system using one or more sensors, comparing the first pump characteristic data to the second pump characteristic data sensed in the flow system, and determining a health of the pump based on the comparison of the first pump characteristic data to the second pump characteristic data.

Abstract: A metering valve spool controls a volume of fuel passing through a metering valve. The spool has a forward face. A line from a pump has a connection into a chamber. The face of the metering valve spool may contact a seal to block flow into the chamber. The metering valve is connected to a pressure regulating valve. The pressure regulating valve is to be connected to a combustor. A control selectively moves the metering valve spool to control a volume of fuel delivered from the chamber to the pressure regulating valve. The control is also programmed to move the metering valve spool to a position where a forward face of the metering valve spool seals on the seal to block flow from the pump from reaching the pressure regulating valve, and also from reaching the tap. A gas turbine engine is also disclosed.